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Salivary Nickel and Chromium Levels in Orthodontic Patients with and Without Periodontitis: a Preliminary Historical Cohort Study.
Amini, F, Asadi, E, Hakimpour, D, Rakhshan, A
Biological trace element research. 2019;(1):10-15
Abstract
Many periodontal patients may need orthodontic treatment. Alterations in oral environment particularly the reduction of pH in periodontal patients could affect metal ion release from orthodontic appliances. However, there is no study on metal ion release in periodontal patients. The aim of this preliminary study was to comparatively evaluate, for the first time, salivary levels of nickel and chromium in periodontal patients (versus healthy controls) under orthodontic treatment for 2 months. In this in vivo study, 40 subjects were evaluated. Patient selection and standardization of orthodontic treatment protocols were prospectively designed and performed. Two groups of n = 20 each (control: healthy orthodontic patients, cohort: orthodontic patients with periodontitis) underwent similar protocols of fixed orthodontic treatment for 2 months. After 2 months, salivary nickel and chromium concentrations of the case and cohort groups were measured using inductively coupled plasma mass spectrometry (ICP-MS). The values were compared between the two groups using t test. There were 10 men and 10 women in each group. The mean age of patients was 34.6 ± 3.6 years old. The salivary level of nickel was 338.2 ± 235.5 ng/ml and 182.8 ± 116.5 ng/ml in the cohort and control groups, respectively (P = 0.0118). The salivary level of chromium was 7.4 ± 3.15 ng/ml in the cohort and 6.35 ± 2.39 ng/ml in the control group (P = 0.2214). Salivary level of nickel might be considerably higher in periodontal patients undergoing 2 months of orthodontic treatment compared to orthodontic patients with healthy gingivae.
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2.
The effect of stress on salivary metal ion content in orthodontic patients.
Amini, F, Rahimi, H, Morad, G, Mollaei, M
Biological trace element research. 2013;(3):339-43
Abstract
Psychological stress can alter the environment in favor of corrosion of orthodontic alloys by changing the properties of saliva. This study aimed to assess the effect of stress induction on salivary nickel and chromium content in fixed orthodontic patients. Thirty patients were enrolled in this experiment. Saliva sample collection was performed at four time points: T1, before insertion of orthodontic appliances; T2, 3 months after the initiation of orthodontic treatment, before induction of stress; T3, 15 min following the induction of stress by Trier Social Stress Test; and T4, 30 min following the induction of stress. Ion content was measured by atomic absorption spectrophotometry. The obtained data were analyzed by repeated measures analysis of variance (ANOVA) and post hoc Bonferroni test. The mean amount of salivary nickel increased from 11.9 ± 5.1 μg/L at T1 to 14.1 ± 5.3 μg/L at T4. This increase was found significant only at T4 comparing to T1. The average salivary chromium content changed from 4.1 ± 2.3 μg/L at T1 to 5.1 ± 3.3 μg/L at T4. None of the differences were significant for chromium. In conclusion, induction of stress in this study led to a significant increase in nickel release from orthodontic appliances into saliva. The salivary chromium content however was not significantly altered, yet gradually increased.
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3.
A clinical trial to evaluate the effects of prophylactic fluoride agents on the superelastic properties of nickel-titanium wires.
Vo, J, Chudasama, DN, Rinchuse, DJ, Day, R
World journal of orthodontics. 2010;(2):135-41
Abstract
AIM: To study the effects of a prophylactic fluoride regimen on the mechanical properties of nickel-titanium (Ni-Ti) archwires under clinical conditions. METHOD The unloading properties of 100 Ni-Ti wires were tested using a three-point bending test at five deflections (0.5 mm, 1.0 mm, 2.0 mm. 3.0 mm, and 3.1 mm). Sixty-six 0.016 3 0.022-inch Ni-Ti wires were tested after being used intraorally for 6 weeks using two protocols. Thirty-three wires were evaluated after the use of fluoride-containing Crest toothpaste (sodium fluoride 0.243%, 0.15% w/v fluoride ion) and Equate fluoride rinse (sodium fluoride 0.05%, fluoride ion 0.0226%). Another 33 wires were examined after a nonfluoridated natural toothpaste (Tom's of Maine; calcium carbonate, xylitol, myrrh, propolis, sodium lauryl sulfate, carrageenan, spearmint and peppermint oils, glycerin, and water) was used. Another 34 Ni-Ti wires served as a control; they were tested as received. Statistical analyses were carried out with a linear-mixed model (analysis of variance [ANOVA]). RESULTS Force degradation occurred within both groups of intraorally used wires but not in the unused archwires. When compared to unexposed wires, those with fluoride exposure exhibited slightly higher force degradation at 3.1 and 3.0 mm deflection, but they displayed less force degradation at 0.5 and 1.0 mm deflection. CONCLUSIONS Topical fluoride regimens decreased the unloading property of Ni-Ti wires at higher deflections but increased it at lower deflections.
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4.
A clinical trial of oral hyposensitization in systemic allergy to nickel.
Schiavino, D, Nucera, E, Alonzi, C, Buonomo, A, Pollastrini, E, Roncallo, C, De Pasquale, T, Lombardo, C, La Torre, G, Sabato, V, et al
International journal of immunopathology and pharmacology. 2006;(3):593-600
Abstract
Nickel allergy is the most common contact allergy. Some nickel-sensitive patients present systemic (cutaneous and/or digestive) symptoms related to the ingestion of high nickel-content foods, which significantly improve after a specific low nickel-content diet. The etiopathogenetic role of nickel in the genesis of systemic disorders is, furthermore, demonstrated by the relapse of previous contact lesions, appearance of widespread eczema and generalized urticaria-like lesions after oral nickel challenge test. The aim of this study is to investigate the safety and efficacy of a specific oral hyposensitization to nickel in patients with both local contact disorders and systemic symptoms after the ingestion of nickel-containing foods. Inclusion criteria for the recruitment of these patients were (other than a positive patch test) a benefit higher than 80% from a low nickel-content diet and a positive oral challenge with nickel. Based on the previous experiences, our group adopted a therapeutic protocol by using increasing oral doses of nickel sulfate associated to an elimination diet. Results have been excellent: this treatment has been effective in inducing clinical tolerance to nickel-containing foods, with a low incidence of side effects (gastric pyrosis, itching erythema).
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5.
Hypersensitivity to metals in orthodontics.
Menezes, LM, Campos, LC, Quintão, CC, Bolognese, AM
American journal of orthodontics and dentofacial orthopedics : official publication of the American Association of Orthodontists, its constituent societies, and the American Board of Orthodontics. 2004;(1):58-64
Abstract
To study the incidence of hypersensitivity to orthodontic metals, patch tests were carried out before and 2 months after the placement of orthodontic appliances in 38 patients (17 male, 21 female). The tested substances were cobalt chloride, copper sulfate, potassium dichromate, iron sulfate, manganese chloride, molybdenum salt, nickel sulfate, and titanium oxide. Eight strips containing the test substances were positioned on the patients' backs. They were removed after 48 hours and assessed by a dermatologist at 48 and 72 hours after antigen application. The obtained data were analyzed by the chi-square test and McNemar's chi-square test. Statistically significant positive reactions were observed for nickel sulfate (21.1%), potassium dichromate (21.1%), and manganese chloride (7.9%); reactions to nickel sulfate had the greatest intensity. No differences were observed between the reactions before and after placement of the orthodontic appliances; this indicates that they did not sensitize the patients or affect their tolerance to these metals during the study period. No statistical difference was observed regarding sex for any evaluated substance, although a greater tendency to positivity to nickel sulfate was observed among female patients and to potassium dichromate in male patients.
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6.
Nickel release after implantation of the Amplatzer occluder.
Ries, MW, Kampmann, C, Rupprecht, HJ, Hintereder, G, Hafner, G, Meyer, J
American heart journal. 2003;(4):737-41
Abstract
BACKGROUND Transcatheter closure of atrial septal defects is a new and less traumatic technique than open heart surgery. In recent years, patients with a patent foramen ovale sustaining potential paradoxical embolism have also become candidates for interventional closure devices. One of the more popular occluding devices is the Amplatzer septal occluder, which, like many other occluders, is made of nitinol. Nitinol-based alloys are widely used in medical products, for example, in orthopedics and orthodontics. However, the clinical use of nitinol, which contains 55% nickel, is still controversial because of concerns about its biocompatibility. Therefore, we examined the systemic nickel release after implantation of the Amplatzer occluder. METHODS AND RESULTS In 67 patients with no history of nickel sensitivity, blood samples were taken 24 hours before and 24 hours, 1, 3, and 12 months after occluder implantation. Nickel serum concentrations were measured by atomic absorption spectrometry; a value of <2 ng/mL of nickel was considered to be normal. A rise in mean serum levels of nickel was observed, from 0.47 ng/mL before implantation to 1.27 ng/mL (24 hours after), to a maximum of 1.50 ng/mL 1 month after implantation, which was statistically significant (P =.008 and P = 0.022, Wilcoxon Test). During follow-up, the values decreased to those measured before implantation. CONCLUSIONS Nickel seems to be released from the device, causing a systemic rise in serum levels of nickel, possibly until a calcium-phosphate layer has formed on the passive oxide film of the device or until endothelialization is complete. Possible biological effects should be considered, particularly in young patients or patients with nickel hypersensitivity.
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7.
Efficacy of topical corticosteroids in nickel-induced contact allergy.
Hachem, JP, De Paepe, K, Vanpée, E, Bogaerts, M, Kaufman, L, Rogiers, V, Roseeuw, D
Clinical and experimental dermatology. 2002;(1):47-50
Abstract
In this study we used the nickel contact allergy patch (CAP) test to investigate the effect of topical corticosteroids on allergic contact dermatitis (ACD). On day 1, three CAP tests were applied for 48 h on the forearms of 20 female volunteers with a known nickel ACD. CAP of the right forearm contained 5% nickel, and of the left forearm physiological saline. Clinical scoring, transepidermal water loss and skin hydration were measured on day 1 before CAP application, on day 4 (0, 2 and 6 h) after ACD and from days 5 to 8 (0 h). A topical corticosteroid and its vehicle were applied twice daily starting from day 4 on two ACD sites. Transepidermal water loss values were significantly decreased on the topical-corticosteroid-treated sites in the early phase of ACD (day 4, 6 h after the first application) while clinical efficacy showed significant improvement on days 7 and 8. The vehicle was found to improve skin hydration only on day 8. In conclusion the topical corticosteroid improved the skin barrier function in the early inflammatory phase of ACD (day 4, 6 h). The lack of improvement in transepidermal water loss in the later phase of ACD might be accounted for by the secondary effects of the corticosteroid on proliferation and differentiation of keratinocytes.